The Air Force’s proposed budget for fiscal 2014 calls for cutting 2,640 airmen next year, but the budget could take a major hit if Congress allows steep cuts to defense spending to continue next fiscal year.

The proposed personnel cuts are far below what the Air Force proposed for this fiscal year, but the budget does not reflect the steep cuts to defense spending known as “sequestration” that took effect in March.

Since then, the Air Force has slashed flying hours, stood down squadrons and taken other extreme measures to have enough money to get through the next six months. Sequestration will last for 10 years unless lawmakers reach an agreement on taxes and spending.

It is difficult to speculate what further cuts will be necessary if sequestration lasts into fiscal 2014, said Maj. Gen. Ed Bolton, deputy assistant Air Force secretary for budget.

“We’re not going to get out of this problem by reducing a few slots here or a few slots there,” Bolton told reporters. “It’s going to have to take some significant change, and so a slight trimming is not going to be the answer.”

The Defense Department is conducting a strategic review due at the end of May that will look into the possibility that Congress fails to reach a grand bargain on the budget and sequestration remains law, Defense Secretary Chuck Hagel said.

“We are living in a world of complete uncertainty,” Hagel said at a news conference on Wednesday.

Right now, the proposed budget would cut 1,860 active-duty airmen, 300 from the Air National Guard and 480 from the Reserve, budget documents show.

As it continues to grapple with fiscal challenges, the Air Force will take a look at the need for more voluntary and involuntary measures to meet its end strength requirements, said Air Force spokesman Maj. Matthew Hasson.

“The objective of our FY14 Force Management strategy is to continue to maximize voluntary programs first in order to minimize the need for involuntary measures,” Hasson said in an email.

Up to 4,300 airmen may be forced out of the service by May 31 under date-of-separation rollbacks so the Air Force can make fiscal 2013’s end strength requirements.

Meanwhile, the Air Force is facing personnel shortages this fiscal year in the airfield operations, intelligence, civil engineering and public affairs career fields, budget documents show.

Right now, about 17 percent of active-duty airmen serve in “stressed” career fields that are undermanned and hard to fill due to operational demands and high deployment rates, according to the budget.

The top stressed career fields for enlisted airmen include airborne cryptologic linguists/ISR operators, operations intelligence and fusion analysts. For officers, they include helicopter pilots, special tactics and intelligence.

The proposed budget calls for $14.4 billion in pay and allowances for enlisted airmen and $6.7 billion for officers, according to the budget documents. That includes $42.6 million in incentive pays and $341.8 million in special pays for enlisted airmen and $206.2 million in incentive pays and $303.6 million in special pays for officers.

For this fiscal year, Congress appropriated $40.9 million in incentive pays and $439.7 million in special pays for enlisted airmen and $218.4 million in incentive pays and $327.2 million in special pays for officers.

The figures for this fiscal year include wartime funding. The Defense Department expects to submit its wartime funding budget in a month.

One reason the amounts are so much higher this fiscal year is they include wartime funding. The Defense Department has not yet submitted a budget for such funding.